The primary objective of this study was to evaluate the efficacy and safety of initiation of edaravone dextivel therapy compared with placebo in patients with acute ischaemic stroke (early and late) and to explore the optimal time window for "brain cell protective therapy" of edaravone dexborneol.

This is a multicentre, randomized, double-blind, placebo-controlled trial that aims to investigate the efficacy and safety of (early and late) initiation treatment of Edaravone Dexborneol versus placebo in patients with acute ischemic stroke, and to explore the optimal time window for "brain cell protective therapy" of Edaravone Dexborneol. Patients who were eligible to the inclusion criteria and ineligible to the exclusion criteria will be stratified by time to trial drug: early (<3 hours) and late (3-6 hours). Then each layer will be randomly assigned into two groups by a 1:1 ratio after the ICF was received. Patients in one arm will be given 15ml edaravone and dexborneol concentrated solution for injection (37.5mg, containing edaravone 30mg and dexborneol 7.5mg) twice a day for 10-14 days, and those in the other arm will be given an equivalent placebo drug. All patients will be followed up for 90 days. The primary outcome is the proportion of modified Rankin Scale 0-2 and the safety outcome is the proportion of severe adverse events.

Inclusion Criteria:

• Age 18-80 years old, gender is not limited;
• Clinically confirmed acute ischemic stroke;
• Within 6 hours of the onset of this stroke;
• NIHSS score of 4-24 at enrollment;
• mRS score before onset≤ 1 point;
• Subject and subject's agent are able and willing to sign informed consent.

Exclusion Criteria:

• CT indicates intracranial hemorrhagic diseases, such as hemorrhagic stroke, subdural hematoma, ventricular hemorrhage, or subarachnoid hemorrhage, etc.;
• Previously known severe liver or kidney insufficiency (ALT or AST is greater than 3.0×ULN; serum Creatinine (SCr) is greater than 1.5×ULN, Creatinine Clearance (CrCl) is less than 50 ml/min or dialysis;
• Systolic blood pressure≥220 mmHg or <90mmHg；
• Recent stroke within prior 1 month；
• Hypersensitive to edaravone, (+)-2- dexborneol or auxiliary materials;
• Prior receipt of edaravone or any other neuroprotective drugs;
• History of congenital or acquired hemorrhagic disease, coagulation factor deficiency disease, or thrombocytopenic disease, etc.;
• Pregnancy, lactation, or planned pregnancy within 90 days;
• Those who cannot complete informed consent or follow-up treatment due to severe mental disorder or dementia;
• Those with a malignant tumor, severe systemic diseases, or predict survival time <90 days;
• Participate in another interventional clinical study within 30 days before randomization or participate in another interventional clinical study;
• The investigators consider the patients are not suitable for this trial.